Anatomy and Asana ezine by Susi
The Sacro-Iliac JointThanks for your questions Bud, from Calgary.

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The sacroiliac joint is located at the base of the spine. Specifically,
it describes where the sacrum (the triangular piece of bone at the base
of the spine) meets the ilium (part of the pelvis). Much of the time
people refer to the sacroiliac joint as the SI joint. You can see the details
of this joint in the picture below (thanks to www.allaboutbackpain.com).
Throughout this ezine, I will be referring to the SI joint in the singular. Keep
in mind, though, that there are 2 - one on either side of the sacrum (see
below).

The SI joint shares some similarities with other joints, however, there is
an important difference that you need to be aware of. Like most joints, the
SI joint is supported by ligaments. They are located in the front and back
of the joint, as well as at the lower portion of the sacrum. Unlike most joints,
there arent any muscles that directly cross over the SI joint to support
it. Therefore, direct support comes from the ligaments. These ligaments
help to keep the sacrum in place.

Sometimes, joints and ligaments can experience injury. When this happens at
the SI joint, the little movement that occurs naturally, may become too great
(hypermobile) causing the joint to become unstable, or the movement may become
too limited (hypomobile) causing the joint to become fixed.

For example, hypermobility commonly occurs after pregnancy. During pregnancy
the hormone relaxin causes the ligaments to become more lax, permitting more
movement at the joint. If the laxity of the ligaments is excessive the joint
itself can become hypermobile and unstable.

What does this have to do with Yoga?

Hyper or hypo mobility at the SI joint can be a contributing factor in back
and butt pain, and these symptoms can be the catalyst for people coming to
Yoga.

Keep the following in mind:

· Because of its placement in the
body, the SI joint acts as a bridge in transmitting the forces from the upper
body to the pelvis, hips and legs.
· Even though there are no muscles
directly supporting the joint, the muscles that attach to the sacrum or the
ilium will have an indirect effect on the functioning and balance of the joint.
These include the hamstrings, piriformis, gluteus maximus, and erector spinae.
If these muscles are tight or weak they can affect the functioning of the
SI joint.
· Because there are 2 SI joints,
the joint mobility or strain can occur more on one side than the other.

If you have pain as the result of the SI joint:

· Seek out a manual physiotherapist
or chiropractor to ensure that Yoga moves are okay for your body at this time.
· Seek out a Yoga instructor who
has a great eye for alignment and can help you feel the proper pelvic and
lumbar spine alignment. Proper alignment will help alleviate strain, as well
as strengthening or stretching muscles which, out of habit, are out of balance.

If you are Yoga teacher:

· Be vigilant with your students
who have SI joint pain to ensure their postures are aligned. Be sure they
are moving through their pain free range of motion.

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The intent of this article to help you further your understanding
and usability of anatomy and asana. Please email me with any
questions. I am currently working on a manual of anatomy and asana, and
your questions will help me to explain concepts in the clearest
way.
You can email me at yoga@functionalsynergy.comFor
Anatomy and Asana workshops, please visit www.functionalsynergy.com